Alexis Powell, the second sister of Isaiah Powell, looks up while sobbing after giving testimony during the sentencing of Dylan Yang at the Marathon County Courthouse, October 19, 2016. Yang, now 16, was convicted in the stabbing death of Isaiah Powell, 13, in 2015. Jacob Byk/USA TODAY NETWORK-Wisconsin

Hailie Fleischman, cousin of Isaiah Powell, fights back tears as she listens to testimony during the sentencing of Dylan Yang at the Marathon County Courthouse, October 19, 2016. Yang, now 16, was convicted in the 2015 stabbing death of Isaiah Powell, 13. Jacob Byk/USA TODAY NETWORK-Wisconsin

Cherry Kiper, grandmother of Isaiah Powell, tries to remain calm during the sentencing of Dylan Yang at the Marathon County Courthouse, October 19, 2016. Yang, now 16, was convicted in the stabbing death of Isaiah Powell, 13, in 2015. Jacob Byk/USA TODAY NETWORK-Wisconsin

A tear dangles on the nose of Hailie Fleischman during thesentencing ofDylan Yang at the Marathon County Courthouse, October 19, 2016.Yang, now 16, was convicted in the 2015 stabbing death of Isaiah Powell, 13. Powell was Fleischman's cousin. Jacob Byk/USA TODAY NETWORK-Wisconsin

Dylan Yang supporters comfort one another outside the Marathon County Courthouse, October 19, 2016. Yang, now 16, was sentenced to 13 years in prison in the 2015 stabbing death of Isaiah Powell, 13. Jacob Byk/USA TODAY NETWORK-Wisconsin

Zong Khang Yang, an international human rights activist, waits in line to enter the courtroom for the sentencing of Dylan Yang, October 19, 2016. He traveled from Saint Paul, Minn. to see the sentencing. Jacob Byk/USA TODAY NETWORK-Wisconsin

Dylan Yang's therapist, Tracey Anne Schindler, tells a judge Yang was artistic and a good student but that he also struggled to control his anger when taunted with racial slurs. Jacob Byk/USA TODAY NETWORK-Wisconsin

WAUSAU – When Dylan Yang was sentenced in 2016 to over a decade in prison for fatally stabbing 13-year-old Isaiah Powell, a judge ordered him to write letters of apology to the victim's family.

Over two years later, Powell's grandparents Tim and Sherry Kiper say the family still hasn't gotten a written apology from Yang.

But Yang did recently write a letter, however.

In a message penned from prison and posted Wednesday to the Facebook page Stay Strong Dylan Yang, the now 19-year-old thanked the hundreds of people who showed up to protest before he was sentenced in October 2016 to serve 13 years in prison for first-degree reckless homicide.

"I was amazed to see so many people there to help fight," Yang wrote. "I was in tears when I saw you all on the news. Seeing how many people were there to support made me cry tears of happiness. I didn’t know that there were so many people who cared. I thought that me and family were all alone."

Hundreds of people gathered outside the Marathon County Courthouse in Wausau on the day of Yang's sentencing to protest the way his case was handled by the court system. Many thought Yang should have been tried as a juvenile, not an adult, and that he was treated unfairly by the justice system from the beginning of the case, when a judge set a $1 million cash bond. Yang was 15 when prosecutors say he stabbed Powell.

Buy Photo

Hundreds of demonstrators rally Tuesday afternoon at The 400 Block in downtown Wausau in a peace march inspired by the guilty verdict against 16-year-old Dylan Yang, who was convicted of homicide in March. Marchers walked past the Wausau Police Department, the Wausau School District’s administration building and the Marathon County Courthouse.(Photo: T'xer Zhon Kha/USA TODAY NETWORK-Wisconsin)

According to a criminal complaint, Yang and Powell had exchanged messages on social media that escalated into a physical brawl in which Powell and a group of his friends confronted Yang and his friends one Friday evening outside a house in Wausau. Police said Powell had a BB gun and shot multiple times at Yang and his friends. Yang went into the house, grabbed a knife and stabbed Powell twice; he later died from his injuries.

Later on in his letter, Yang wrote that even though he chose not appeal his conviction, he hasn't given up and continues fighting from prison. He said he's been reading about the law, doing research and talking with prison staff and other inmates to see what else he can do.

"You all will be in my heart…each and every one of you guy(s)," Yang writes at the end of his letter. "One day I’d like to meet you all. I love you with all my heart and I wish the best for you all."

Yang moved April 11 from Columbia Correctional Institution, a maximum-security prison in Portage, to Stanley Correctional Institution, a medium-security facility, according to the Wisconsin Department of Corrections.

Isaiah Powell died Friday after he was stabbed during a fight.(Photo: Contributed photo)

'He doesn't have any remorse'

Sherry Kiper called Yang's letter "selfish" and "pathetic." Nowhere in the letter did Yang mention Powell or apologize for what he did, she said. She and her husband say they think it was wrong for Yang to write a letter thanking his supporters when they say he still hasn't written to the family, even though a judge ordered him to do so.

"He doesn't have any remorse," Tim Kiper said. "The only time Dylan showed anything, any emotion, was when he found out he was going to prison."

Tim Kiper said he feels Yang's 13-year prison sentence is too short, though no amount of time behind bars could ever make up for his grandchild's death. Yang gets to talk to his family, get an education while in prison and one day will be free and able to build a life for himself, Tim Kiper said. But Powell and his family will never have those opportunities.

All Powell's family has is his headstone in the ground, a lock of his hair and 13 years of memories.

"If they had given him 100 years it wouldn't have been enough for me," Tim Kiper said.

Buy Photo

Family and friends of Isaiah Powell marched through downtown Wausau on June 10, 2016 with the message, "Isaiah's not a bully." He died at age 13 in a fight with other boys after he was stabbed twice in the back by Dylan Yang.(Photo: Nora G. Hertel/USA TODAY NETWORK-Wisconsin)

The family got together and celebrated what would have been Powell's18th birthday on March 26 with dinner and cake — but without their son, grandson and brother there with them.

"At least they got their son," Sherry Kiper said of Yang's family. "Shannon (Isaiah's mom) doesn't have her son."

Tim Kiper said the family doesn't condone what Powell did the day he was killed and if he was still alive, he would agree what he did was wrong. He thinks his grandson probably would've forgiven Yang. But Tim never will.